Messages show up everywhere. Texts, answering machines, mobiles, tablets, emails… and people routinely return calls. And sometimes they’re important, carrying information about sick family members, problems that need to be resolved and other urgent issues.

Which is what makes the well-known 809 area code scam work.

It’s been around for years: Someone sets up an overseas number with the area code, puts on a recording that is painstakingly laborious and slow, and then leaves messages by the thousands – referencing some vague danger for a relative or threat to a credit report – hoping people call.

The hook as that the number is linked to a pay-per-call setup, so people who call are automatically billed.

Viral Internet warnings say the billing is $2,400 per minute, but the experts say it’s more often $25.

But American consumers facing a “legitimate” bill from overseas have an uphill climb to fight it, after all, they did make the call.

The hoaxbuster Snopes says the current versions aren’t as prevalent as they used to be.

“Once the victim placed a call, he was typically connected to a fax machine, lengthy recorded message, or a pay-per-call service with a hefty-up-front fee, all intended to keep him on the line as long as possible while the clock ticked and the charges mounted,” the site reports. “The scammer’s foreign phone company then billed the victim via the latter’s local phone company, splitting the monies collected with the scammers and leaving the victim little or no recourse since the foreign phone company operated outside U.S. jurisdiction and was therefore not subject to U.S. laws (especially regulations requiring the operators of pay-per-call services to notify callers in advance how much they will be charged for each call and offer them an opportunity to hang up without incurring any charges.)”

Snopes notes that it’s not just 809 area codes, either, nowadays and cites advice from the Federal Communications Commission that 284, 876 and others have been used, too. The federal agency says the best defense is to check all area codes before returning calls, and if a person doesn’t routinely make international calls, that function can be blocked on telephones.

That, the FCC said, would prevent problems with those 809 calls to the Dominican Republic, the 284 calls to the British Virgin Islands and the 876 calls to Jamaica.

AT&T has more specific advice: “Return calls to familiar numbers only. As a general rule, return calls from numbers that contain familiar or recognizable area codes,” the company advises. “Carefully read your telephone bill. Make sure that you only receive charges from your provider of choice.”

Verizon agrees: “If you don’t recognize the phone number or area code, don’t return the call. In general don’t respond to such a message in any situation unless you are absolutely sure you know the person or the number you are calling.”

Snopes noted that the many warnings that have been issued appear to have been largely successful, moving the 809 warnings into the realm of “online scarelore.”

“Not every phone number in the 809 area code is part of this scam,” the site reported.